Gas compressor

ABSTRACT

To provide a gas compressor capable of reducing the pressure loss of the oil containing high-pressure refrigerant gas and achieving an improvement in compressor performance. In a construction in which oil containing high-pressure refrigerant gas discharged from cylinder discharge holes passes through discharge chambers and discharge gas passages to be led to oil separation filters side attached to an oil separator, the discharge gas passages are linear, whereby the oil containing high-pressure refrigerant gas flows smoothly through the discharge gas passages, and the pressure loss of the oil containing high-pressure refrigerant gas is reduced. Further, the height of inlet openings of the discharge gas passages are set to be the same as the height of outlet openings, whereby the discharge gas passages extend horizontally and are of the shortest length, thereby further reducing the pressure loss of the high-pressure refrigerant gas.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a gas compressor mounted in avehicle as a part of an automotive air conditioner system or mounted inan exterior unit as a part of an air conditioning system and, inparticular, to a gas compressor in which the pressure loss of an oilcontaining high-pressure refrigerant gas is reduced to thereby achievean improvement in compressor performance.

[0003] 2. Description of the Related Art

[0004] As shown in FIG. 3, a conventional example of a gas compressor ofthis type has a cylinder 1 having a substantially elliptical innerperipheral configuration, side blocks 2 and 3 being respectively mountedto the end surfaces of the cylinder 1. A rotor 4 is arranged inside thecylinder 1 between the front and rear side blocks 2 and 3. The rotor 4is horizontally positioned so as to be rotatable through a rotor shaft 5integrally provided at its axial center and bearings 6 and 7 of the sideblocks 2 and 3 supporting the same.

[0005] As shown in FIG. 4, five slit-like vane grooves 8 are formedradially in the rotor 4, and vanes 9 are respectively attached to thesevane grooves 8, the vanes 9 being capable of jutting out from the outerperipheral surface of the rotor 4 toward the inner wall of the cylinder1 and retracting into the rotor 4.

[0006] The interior of the cylinder 1 is divided into a plurality ofsmall chambers by the inner wall of the cylinder 1, the inner surfacesof the side blocks 2 and 3, the outer peripheral surface of the rotor 4,and the side surfaces of the forward end portions of the vanes 9. Thesmall chambers thus defined constitute compression chambers 10, whosevolume is repeatedly varied as the rotor 4 rotates in the direction ofthe arrow RD.

[0007] In the case where the volume of the compression chamber 10varies, at the time of increasing the volume of the compression chambers10, the oil containing low-pressure refrigerant gas in a suction chamber11 is introduced into the compression chambers 10 through suctionpassages 12 of the cylinder 1 and inlets 13 of the side blocks 2 and 3.Then, when the volume of the compression chambers 10 starts to decrease,the refrigerant gas in the compression chambers 10 starts to becompressed due to the volume reduction effect. Thereafter, when thevolume of the compression chambers 10 approaches to its minimum,discharge valves 15 of cylinder discharge holes 14 provided near theelliptically short diameter portion of the cylinder 1 are opened by thepressure of the compressed oil containing high-pressure refrigerant gas.As a result, the oil containing high-pressure refrigerant gas in thecompression chambers 10 are discharged through the cylinder dischargeholes 14.

[0008] The oil-containing high-pressure refrigerant gas dischargedthrough the cylinder discharge holes 14 flows through discharge chambers16 and discharge gas passages 24 in the outer periphery of the cylinder1 before it is led to oil separation filters 18-1 of an oil separator 18mounted to the rear portion of the side block 3.

[0009] The oil containing high-pressure refrigerant gas led to the oilseparation filters 16-1 is separated into an oil component and a gascomponent as a result, for example, of striking against wire-meshesconstituting the oil separation filters 18-1. The gas component flowsinto a discharge chamber 19, and is then supplied from the dischargechamber 19 to the condenser side of the air conditioning system by wayof a discharge port of a compressor case (not shown). On the other hand,after the separation, the oil component drips down into an oil sump 20at the bottom of the discharge chamber 19 to be stored, and is suppliedto portions where oil is required through an oil passage 21 of the sideblocks 2 and 3 and the cylinder 1. Examples of the portions where theoil is required include the clearances of the bearings 6 and 7, flatgrooves 22 formed on the sides of the side blocks 2 and 3 facing thecylinder, and vane back pressure spaces 23 at the bottom of the vanes 9communicating therewith.

[0010] However, as shown in FIG. 5, the above-described conventional gascompressor adopts a structure in which, to enhance the oil separationperformance, the discharge gas passages 24 of the oil separator 18 arebent twice at right angles to thereby cause the oil containinghigh-pressure refrigerant gas to strike against the inner walls of thegas passages 24 twice. This striking construction provides little or noeffect of improving the oil separation performance. Rather, it involvesan increase in the pressure loss of the oil containing high-pressurerefrigerant gas, which leads to deterioration in the compressorperformance.

[0011] The present invention has been made with a view toward solvingthe above problem in the prior art. It is an object of the presentinvention to provide a gas compressor which can reduce the pressure lossof the oil containing high-pressure refrigerant gas to thereby achievean improvement in compressor performance.

SUMMARY OF THE INVENTION

[0012] To achieve the above object, the present invention relates to agas compressor comprising a cylinder arranged between a pair of sideblocks, a rotor horizontally arranged in the cylinder so as to berotatable, vanes provided so as to be capable of jutting out toward theinner wall of the cylinder from the outer peripheral surface of therotor and retracting therein, compression chambers defined by thecylinder, the side blocks, the rotor, and the vanes, cylinder dischargeholes for discharging refrigerant gas from the compression chambers, adischarge chamber for temporarily storing the refrigerant gas dischargedfrom the cylinder discharge holes, a linear discharge gas passage forguiding the refrigerant gas from the discharge chamber to the downstreamside of the discharge chamber, an oil separator arranged on thedownstream side of the discharge gas passage and having an oilseparation filter for separating the refrigerant gas and the oil fromeach other, and a discharge chamber for temporarily storing therefrigerant gas and the oil separated by the oil separation filter.

[0013] Then, according to the present invention, the discharge gaspassage is made linear, whereby the oil containing high-pressurerefrigerant gas flows smoothly through the discharge gas passage,thereby reducing the pressure loss of the oil containing high-pressurerefrigerant gas.

[0014] Further, present invention relates to a gas compressor, whereinthe height of an outlet opening on the oil separator side of thedischarge gas passage is set to be the same as the height of an inletopening of the discharge gas passage, whereby the discharge gas passageextends horizontally.

[0015] Then, according to the present invention, the oil separator sideopening of the discharge gas passage communicating with the dischargechamber is set to be of the same height as the inlet opening thereof,whereby the discharge gas passage extends horizontally and is of theshortest length, whereby it is possible to further reduce the pressureloss of the oil containing high-pressure refrigerant gas.

[0016] Further, the present invention relates to a gas compressor,wherein the oil separation filter of the oil separator is positionedabove the outlet opening of the discharge gas passage.

[0017] Then, according to the present invention, the oil separationfilter of the oil separator is positioned above the outlet opening ofthe discharge gas passage, so that a large space can be secured for theoil sump below the oil separation filter.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIGS. 1A, 1B, and 1C are an explanatory drawing showing a mainportion of a gas compressor according to the present invention, FIG. 1Ais a front view of a built-in oil separator in the gas compressor, FIG.1B is a rear view thereof, and FIG. 1C is a sectional view taken alongthe line B-B of FIG. 1B.

[0019]FIGS. 2A, 2B, and 2C are an explanatory drawing showing a mainportion of a gas compressor in accordance with another embodiment of thepresent invention, FIG. 2A is a front view of a built-in oil separatorin the gas compressor, FIG. 2B is a rear view thereof, and FIG. 2C is asectional view taken along the line B-B of FIG. 2B.

[0020]FIG. 3 is a sectional view of a gas compressor according to thepresent invention.

[0021]FIG. 4 is a sectional view taken along the line A-A of FIG. 3.

[0022]FIG. 5A, FIG. 5B, and FIG. 5C are an explanatory drawing showingan oil separator mounted in the conventional gas compressor, FIG. 5A isa front view of the oil separator, FIG. 5B is a rear view thereof, andFIG. 5C is a sectional view taken along the line B-B of FIG. 5B.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0023] A gas compressor in accordance with an embodiment of the presentinvention will now be described in detail with reference to theaccompanying drawings.

[0024] The basic construction of the gas compressor of this embodimentis the same as that of the conventional gas compressor shown in FIGS. 3and 4, in which the cylinder 1 is arranged between a pair of side blocks2 and 3 and in which the rotor 4 is horizontally arranged inside thecylinder 1 so as to be rotatable, the vanes 9 being provided so as to becapable of jutting out toward the inner wall of the cylinder 1 from theouter peripheral surface of the rotor 4 and retracting therein. Insidethe cylinder 1, the compression chambers 10 defined by the vanes 9, etc.are provided, and the volume of the compression chambers 10 repeatedlyincreases and decreases as the rotor 4 rotates, whereby the oilcontaining low-pressure refrigerant gas in the suction chamber is takenin and compressed. Further, the compressed oil containing high-pressurerefrigerant gas is discharged through the cylinder discharge holes 14 asin the prior art. Thus, the component which are the same as those of theconventional gas compressor will be indicated by the same referencenumerals, and a detailed description of such components will be omitted.

[0025] In the gas compressor of this embodiment also, the oil containinghigh-pressure refrigerant gas discharged through the cylinder dischargeholes 14 as described above flows through the discharge chamber 16 andthe discharge gas passages 24 and is led to the oil separation filters18-1 attached to the oil separator 18. As shown in FIG. 1, in the gascompressor of this embodiment, such discharge gas passages 24 are formedinto a linear shape so as to realize linearization thereof.

[0026] That is, one end 24 a of each discharge gas passage 24 opens onthe discharge chamber 16 side, and the other end 24 b thereof opens onthe oil separation filter 18-1 side of the oil separation filter 18. Thesection between one end (inlet opening) 24 a of each discharge gaspassage 24 and the other end (outlet opening) 24 b thereof extends in acompletely straight line, without being bent anywhere. Furtherparticular explaining, the discharge gas passage 24 is formed linearwhichever direction from seen, for example, front or rear view shown inFIG. 1B, plane view like shown in FIG. 1C, and side view like shown inFIG. 3.

[0027] Each discharge gas passage 24 is formed extending from thedischarge chambers 16 to the oil separator 18 through the rear sideblock 3 in a punching manner. In this embodiment, the angle at which thedischarge gas passage 24 reaches the oil separator 18 is not alsochanged.

[0028] That is, as shown in FIG. 5, each discharge gas passage 24 in theconventional gas compressor is bent substantially at right anglesimmediately after entering the oil separator 18 through the rear sideblock 3, whereas, as shown in FIG. 1, each discharge gas passage 24 ofthe gas compressor of this embodiment is not bent immediately afterentering the oil separator 18 through the rear side block 3, and isformed linear.

[0029] Referring to FIG. 4, in the case of the gas compressor of thisembodiment, two cylinder discharge holes 14, two discharge chambers 16,two discharge gas passages 24, and two oil separation filters 18-1 ofthe oil separator 18 are provided. This is due to the substantiallyelliptical inner peripheral configuration of the cylinder 1 and due tothe structure in which five vanes 9 are provided. When the rotor 4 makesone rotation, intake operation and compressing operation are executed attwo positions in the cylinder 1, and the portions of the oil containinghigh-pressure refrigerant gas respectively compressed at the twopositions are separately guided to the oil separator 18.

[0030] As stated above, the two discharge gas passages 24 and 24 areboth linear. However, they are not parallel to each other but are in av-shaped arrangement in which they are directed toward the two oilseparation filters 18-1 and 18-1 arranged side by side at the center ofthe oil separator 18.

[0031] In the gas compressor of this embodiment also, the oil containinghigh-pressure refrigerant gas discharged through the cylinder dischargeholes 14 is led to the oil separation filters 18-1 of the oil separator18 through the discharge chambers 16 and the discharge gas passages 24.When, as in this embodiment, the discharge gas passages 24 are attemptedto be linear, the oil containing high-pressure refrigerant gas can besmoothly transferred from the cylinder discharge holes 14 to the oilseparation filters 18-1, whereby the pressure loss of the oil containinghigh-pressure refrigerant gas is reduced, and the compressor performanceis improved.

[0032] It is to be noted that the pressure loss of the oil containinghigh-pressure refrigerant gas also depends on the sectional area of thedischarge gas passages 24; the larger the sectional area of thedischarge gas passages 24, the less the pressure loss of the oilcontaining high-pressure refrigerant gas. Thus, it is desirable that thesectional area of the discharge gas passages 24 be set to be as large aspossible.

[0033]FIG. 2 shows a configuration of a gas compressor in accordancewith another embodiment of the present invention. FIG. 2A is a rearelevational view of an oil separator as seen from the rear side, FIG. 2Bis an elevational view of the oil separator as seen from the sideabutting the rear side block, and FIG. 2C is a sectional view takenalong the line B-B of FIG. 2B.

[0034] In this embodiment, in order to further reduce the pressure lossof the oil containing high-pressure refrigerant gas, the height of oneend 24 a of each discharge gas passage 24, that is, the height of thedischarge chamber 16 side inlet opening constituting the inlet of thedischarge gas passage 24, is set to be the same as the height of theother end 24 b of the discharge gas passage 24, that is, the height ofthe oil separator 18 side outlet opening, whereby each discharge gaspassage 24 connecting the inlet and outlet openings 24 a and 24 bextends horizontally and is of the shortest length.

[0035] Thus, in this embodiment, in which the discharge gas passages 24are of the shortest length, it is possible to restrain at a low levelthe pressure loss of the oil containing high-pressure refrigerant gas,which is discharged from the cylinder discharge holes 14 and led fromthe discharge chambers 16 to the oil separation filters 18-1 of the oilseparator 18 through the discharge gas passages 24.

[0036] Further, since the discharge gas passages 24 extend horizontally,it is possible to minimize the resistance when passing the high-pressurerefrigerant gas therethrough, which also leads to a reduction inpressure loss, thereby achieving a further improvement in compressorfunction.

[0037] As described above, in the gas compressor of the presentinvention, the discharge gas passages are linear, so that the oilcontaining high-pressure refrigerant gas flows smoothly from thecylinder discharge holes to the oil separation filters of the oilseparator through the discharge gas passages, whereby the pressure lossof the oil containing high-pressure refrigerant gas of this type isreduced, thereby achieving an improvement in compressor performance.

[0038] Further, in the gas compressor of the present invention, thedischarge gas passages are formed linearly, and the height of the inletopening communicating with the discharge chamber is set to be the sameas the height of the outlet opening on the oil separator side, wherebythe discharge gas passages extend horizontally and are of the shortestlength,, thereby further reducing the pressure loss of the oilcontaining high-pressure refrigerant gas passing through the dischargegas passages to thereby achieve a further improvement in compressorperformance.

What is claimed is:
 1. A gas compressor comprising: a cylinder arrangedbetween a pair of side blocks; a rotor horizontally arranged in thecylinder so as to be rotatable; vanes provided so as to be capable ofjutting out toward the inner wall of the cylinder from the outerperipheral surface of the rotor and retracting therein; compressionchambers defined by the cylinder, side blocks, rotor, and vanes;cylinder discharge holes for discharging refrigerant gas from thecompression chambers; a discharge chamber for temporarily storing therefrigerant gas discharged from the cylinder discharge holes; a lineardischarge gas passage for guiding the refrigerant gas from the dischargechamber to the downstream side of the discharge chamber; an oilseparator arranged on the downstream side of the discharge gas passageand having an oil separation filter for separating the refrigerant gasand the oil from each other; and a discharge chamber for temporarilystoring the refrigerant gas and the oil separated by the oil separationfilter.
 2. A gas compressor according to claim 1, wherein the height ofan outlet opening on the oil separator side of the discharge gas passageis set to be the same as the height of an inlet opening of the dischargegas passage, whereby the discharge gas passage extends horizontally. 3.A gas compressor according to claim 2, wherein the oil separation filterof the oil separator is positioned above the outlet opening of thedischarge gas passage.